2.4.0.8152 - Disclosure - OTHER BORROWED FUNDS (Details)truefalseIn Thousands, unless otherwise specifiedfalse1false USDfalsefalse$P01_01_2013To06_30_2013http://www.sec.gov/CIK0001493552duration2013-01-01T00:00:002013-06-30T00:00:00pureStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$P01_01_2012To12_31_2012http://www.sec.gov/CIK0001493552duration2012-01-01T00:00:002012-12-31T00:00:00pureStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 3nvsl_BorrowedFundsForRepurchaseAgreementsLineItemsnvsl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalselabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Borrowed Funds For Repurchase Agreements [Line Items]2false 4us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriodus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse1456000014560USD$falsetruefalse2truefalsefalse1928300019283USD$falsetruefalsexbrli:monetaryItemTypemonetaryFor the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, the maximum amount borrowed at any time during the period.No definition available.false2Maximum amount of advances outstanding during the period3false 4us-gaap_ShorttermDebtAverageOutstandingAmountus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse1105400011054falsefalsefalse2truefalsefalse1160800011608falsefalsefalsexbrli:monetaryItemTypemonetaryFor the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, average borrowings during the period.No definition available.false2Average advances outstanding during the period4false 4nvsl_ShortTermDebtWeightedAverageInterestRateDuringPeriodnvsl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.00390.0039falsefalsefalse2truetruefalse0.00470.0047falsefalsefalsenum:percentItemTypepureReflects the average interest rate weighted by the amount of short-term debt outstanding by type or by instrument during the period.No definition available.false0Weighted average interest rate during the period5false 4us-gaap_ShortTermBorrowingsus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse54500005450USD$falsetruefalse2truefalsefalse63940006394USD$falsetruefalsexbrli:monetaryItemTypemonetaryReflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph a -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.(a),16(a)(1)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Subparagraph a(1) -Article 7 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Subparagraph 2, 3 -Article 9 false2Balance outstanding at end of period6false 4us-gaap_ShortTermDebtWeightedAverageInterestRateus-gaap_truenainstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00220.0022falsefalsefalse2truetruefalse0.00450.0045falsefalsefalsenum:percentItemTypepureWeighted average interest rate of short-term debt outstanding.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph b -Article 5 false0Weighted average interest rate at end of periodfalseOTHER BORROWED FUNDS (Details) (USD $)ThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.nvsl.com/role/OtherBorrowedFundsDetails26